98 expedition electrical problems

[desert rat]

Here is where I am:

Replaced battery
still no interior light
disabled security system
started and seemed ok
then starter started activating on its own,
as the rig warmed up the starter tried to engage more frequently
turned the rig on and it started, did not have to go to start, the starter still tried to engauge and the dash readings went to "0", when the starter tried to engauge the readings jumped up and then went away,then the headlights came on high beam and would not go off except on thier own. Idle and all seem OK, but the rest is bizzar!!!!! I also hear several relays under the dash go crazy when the starter acts up and the gauges go down. The remote lock clicker dioes not work, the radio is constantly on, used to go off when the switch was in the off position. I suspect either the PCM module or the switch in the colum....any one else had the same issues????